If the air provided to a power plant on board ship for combustion has been cleansed of moisture and other contaminants, the power plant service life and reliability will be enhanced. This is true of gasoline and diesel engines, and particularly gas turbine engines. In the past, moisture and contaminants have been removed by a moisture separator, one configuration of which includes an inertial vane separator followed by a moisture coalescer which, in turn, is followed by a second inertial vane separator.
Inertial vane separators function to provide a tortuous path for the air flow to force separation of the moisture from the air by turning the direction of the air so quickly that the moisture is separated by the effects of inertia and flows down the vanes of the separator for disposal. The coalescer is formed of a porous mat of fibrous material which acts to coalesce small droplets, which are difficult to separate by inertia. These coalescers are usually fibrous and use woven or nonwoven materials of fine threads typically between 0.010 and 0.001 inch in diameter. The second inertial vane separator acts to separate the coalescer droplets by inertial effects and, since the coalesced droplets are usually greater than 50 microns in diameter, this is easily achieved.
Prior marine moisture separator designs such as those supplied by the Assignee of the present application, Peerless Manufacturing Company of Dallas, Tex., have been limited to air velocities in the range of from about 5 to 30 standard feet per second (sfps). Higher velocities have not been practical because of excessive pressure loss, droplet shattering and subsequent re-entrainment of water droplets. With these limitations, the moisture separator must often be quite a large structure to provide sufficient air flow for power plant operation. The need exists for an enhanced moisture separator system which is capable of separating moisture and contaminants from the air flow at velocities higher than that previously possible. This would allow for a reduced size separator configuration and use of higher performance marine power plants. Thus, the present invention provides the advantages of a more efficient removal of water, allows higher velocities to be used, and permits use of a lighter weight separator.